Durham, N.C. — Genetic testing can show if you are at greater risk of certain cancers, but what if that information on your medical record makes it tougher to get insurance coverage?

Debbie Horwitz said breast cancer runs in her family.

"My mom died of breast cancer in her thirties and my grandmother also had breast cancer," she said.

Horwitz considered a genetic test at Duke to see if she had a mutation in the BRCA 1 or BRCA 2 genes, which indicate a greater risk of breast and ovarian cancer. But about two years ago, she did not have to wonder.

"I was diagnosed with cancer at 32. I'm 34 now," she said. "So when I was finally diagnosed, then I was anxious to be tested."

A child of a genetic carrier has a 50/50 chance of having the same mutation. A positive test can lead to earlier detection through more regular screening. A positive test can also help those with breast cancer know to attack it more aggressively.

With the help of a genetic counselor, Horwitz chose a double mastectomy, instead of a lumpectomy, followed by chemotherapy. Marcom said genetic test results are part of the patient's medical record seen by other doctors and insurers.

Insurers in Great Britain want to use the information to set higher premiums, which raises a lot of fears in the United States. Health officials said insurance discrimination could keep more women from getting the test, but it's not a problem in the United States.

"To this point, they seem to have made a judgement that it's in their interest not to use this information in that way," Marcom said.

Legislation is currently before Congress to prevent insurance discrimination based on genetic testing.